/*
 * ProGuard -- shrinking, optimization, obfuscation, and preverification of Java bytecode.
 *
 * Copyright (c) 2002-2018 GuardSquare NV
 *
 * This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public
 * License as published by the Free Software Foundation; either version 2 of the License, or (at your option) any later
 * version.
 *
 * This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied
 * warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License along with this program; if not, write to the Free
 * Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
 */
package a.gui.proguard.gui.splash;

/**
 * This VariableString produces a String that grows linearly with respect to its Timing, as if it is being written on a
 * typewriter. A cursor at the end precedes the typed characters.
 *
 * @author Eric Lafortune
 */
public class TypeWriterString implements VariableString {
    private final String string;
    private final Timing timing;

    private int cachedLength = -1;
    private String cachedString;

    /**
     * Creates a new TypeWriterString.
     * 
     * @param string the basic String.
     * @param timing the applied timing.
     */
    public TypeWriterString(String string, Timing timing) {
        this.string = string;
        this.timing = timing;
    }

    // Implementation for VariableString.

    public String getString(long time) {
        double t = timing.getTiming(time);

        int stringLength = string.length();
        int length = (int)(stringLength * t + 0.5);
        if (length != cachedLength) {
            cachedLength = length;
            cachedString = string.substring(0, length);
            if (t > 0.0 && length < stringLength) {
                cachedString += "_";
            }
        }

        return cachedString;
    }
}
